Die head



Feb', 10. 1925.

S. A. SOUNDOUKOFF DIE HEAD Filed April 14. 1923 INVENToR Sergei H. Soundoulmf BY 3 e 6MLTORNEY' Patented Feb. 10, 1925.

UNTED STTES SERGEE A. SOUNDOUKGFF, 0F BROOKLYN, YORK.

DIE HEAD.

Application led April 14, 1923. Serial No. 631,980.

To @ZZ whomy @'25 may concern.'

Be 1t known that I, Sereni' A. SoUNDoU- nerr, a citizen of Russia, and a-resident'of Brooklyn, county of'Iings, and State ofv New York, have invented an Improvement in Die Heads,rof which the following is a specification.

This invention relates to a die head.

An object of the invention resides in the provision lof a device of this character in which the chasers are automatically retrieved.l 1

A further object of theinvention resides in the provision of agenerally improved f structure to facilitate the chasing of threads and the retrieving of the chasers.

In the drawing, which y illustrates one form of my invention, i

Figure 1 is an end elevation thereofg" Figure 2 is a longitudinal, sectional view; Figure 3 is an end-A elevationlooking at the opposite end to 'that shown inFigure 1; Figure et is an elevational view, with parts removed, to illustrate the spring-actuating means for retrieving the chasers,"

Figure 5 is a vview partly in elevation, and

partly in section showing the -man`ner in which the cams and cam ring co-operate to control the movements of the chasers;

Figures 6,- 7 'and 8 are detail elevations of the chaser carriers; 'and Figure 9 is a view'o'f a modified form of lock for' the cam ring.' l 7 The embodiment of the Vinvention 'illus` trated in the drawing includes a'diey body 10 having 'a shank 11 with an'axia'l opening 12' therethrough, the shank being teriorly screw-'threaded at one end 13. The opening extends through the die body so as to receive the work being operated upon. This die head is provided with a transverse slot lain which chaser carriers 15 and 16 are slidably mounted.- Chasers 17 are removably and adjustably mounted 'on these carriers 15 and 16 and are held in theirv adliusted positions by set` screws 18, the adjustment of the chasers being attained in a manner which will later appear.

A. cam ring 19 is mounted on a reduced portion 2O of the die body. The relative longitudinal movement of the die body and cam ring in one direction is prevented by a Vflange 21 which is formed by the reduction of the size of the die body vfor the reception of the cainring. The relative longitudinal movement of the cam ring and die body in the opposite direction is prevented by a collar 22 which is retained in place by set screws 23. n

In order to reduce the friction between the die body and the cam ring, so as to permit the free relative'rotation of thesame, I have provided the cam ring with a series of anti-friction bearings preferably in the form of roller bearings 24, which are arranged in the manner illustrated in Figure 5 of the drawings, and which form the bearing surface between the cam ring and the reduced portion 2O of the die body.

A face plate 25 is removably secured to the die body by screws 26 and is provided with a transverse elongated opening 27 for the reception of the chasers 17. This opening registers with the slot 14C in the die body.

The adjustment of the chasers on the carriers 15 and 16, which has heretofore been referred to is 'attained by set screws Q8 shown in Figures 1 and 2.

The chaser'carriers 15 are provided with depending cams 29, the facesSO ofwhich are adaptedv to operate on they roller bearings 2e. The cam ring 19 is. provided with depressions 31,which are adapted to receive the cams 29, so as to permit the outward movements of the carriers and the consequent retrieving of the chasers.`

It will be noticed that where the depressions 31 merge with the inner' face ofthe cam ring, the roller bearings 24 are located so as to facilitate the movement ofthe cams from the depressions and consequently make easy the throwing of the chasers Vinto operation. Y

In order that the carriers 15 and 16 may be moved outwardly, automatically, when the Ycams 29 reach the depressions V.51, so as to retrieve the chasers, I have provided the die body with channels 32, which communicate with openings 33 through the chaser carriers 15. A compound bow spring Seis located in the channel 32 and extends through and finds bearings in the openings 83. This spring in the vform illustrated in Figure L1 of the drawings is formed of one piece of material, bent into `a double bow form with the ends 35 brought together, and with a straight bearing portion 36 opposite the ends. Y t

It will beseen that the endsV may be separated so as to pass the spring through vthe openings 83 of the Chaser carriers, and

it will be further noted that the spring is by the cam ring latch 37. The bow spring bowed on a greater radius than that of the channels, so that when the chaser carriers 15 are moved inwardly, there will be room to permit the further bowing of the spring.

In order that the die body and cam ring may be locked together so that the cams 29 of the carriers will be locked on the high portions of the inner face of the cam ring and be prevented from moving into the depressions 31, whereby the chasers will be held rigidly in their inner or cutting positions, I have mounted a latch 37 on the cam ring 19, which latch engages a notch 33 in the collar 22, which is rigidly associated with the die body.

The latch is held in its locking position by a spring 39. This latch is also provided with a projection 40, which is adapted to engage and bear on the outer face of the cam ring 19, so that the latch is disengaged from the notch 38 the latch member 37 inav be used as a handle to move the cam ring in the die body until the cams 29 are. forced :into the depressions 31 and to subsequently move the cam ring to its initial position where the cams are once more located on the high portions of the inner face of the ring and the chasers are in engagement with the work.

In Figure 9 of the vdrawings I have illustrated a modified form of the latch member which comprises two parts, one a handle 41 which is rigidly attached to the cam ring, and the other a latch member 42, which is pivotally mounted on the handle and is adapted to engage a depression 43 on the collar This latch member 42 is held in engagement with the notch 43 by a spring 44.

It will be seen from the above description that I have provided a die head wherein the chasers will be automatically retrieved upon release of the latch and one which is so constructed that the assembly of the parts will be simple and yet the operation of the chasers in both directions greatly facilitated.

lilhile I have described a particular embodiment of my invention I do not wish to be limited to that embodiment as it is obvious that many changes in the details of construction may be made within the scope of the claims.

The operation of my die head is as follows: The shank 11 is rigidly mounted by means of the screw threads 13 or by a holder into which the shank extends.

'Ihe revolving work is brought toward the head and enters the chasers, which are in the cutting position shown in Fig l. rllhe cams 29 of the chaser carriers 15 and 16 are in the position shown in Fig. 5 with their cam faces 29 on the high part of the cam ring 19 and retained in that position 34, held by the slots 33 in the chaser carriers, is given an increased compression by being further bowed outwardly, this outward bowing resulting from the action of the chaser carriers 15 and 16 when these carriers are brought closer together, for the bow spring 34 is retained in the slots 33 of the chaser carriers and therefore this spring is given an increased compression as these chaser carriers approach each other and a reduced compression as they are separated at the end of the cutting ope-ration or otherwise. Cutting of the screw thread on the work proceeds until the desired length is attained. Vhen this point is reached, the latch 37 is thrown, causing its projection to move from the notch 38 in collar 32. The cam ring 19 is then free to move. The bow spring 34, exerting pressure on the chaser carriers, tends to force them outwardlyT from the center and this same pressure appears between the cam faces of the chaser carriers 29 and t-he cam ring 19 thereby causing cam ring 19 to rotate under the action of the two cam surfaces 29 and 31 (Fig. 5). In the lposition shown in this iigure the cam ring 19 is locked in position by the latch 37 and the die is in the cutting position so that the port-ion 31 of the ring 19 and the cams 29 are not entirely out of contact, that is, the points of these cams 29 do not pass by the anti-friction bearings heretobefore described. Consequently as the bow spring 34 is constantly tending to force these cams 29 apart, there is a corresponding tendency for these cams to slip back into the depressions 31 due to the two cam surfaces being in contact. They are prevented from doing this during the cutting operation because, as just stated, the cam ring 19 is locked by the latch 37. I-Iowever, as soon as this latch 37 is released, and inasmuch as the cams 29 can not rotate, the action resulting from the pressure of the spring 34 is to force the cams 29 into the depressions in cam ring 19 and asthis action takes place the cam ring 19 is necessarily rotated. The chasers are again brought to their cutting position of Fig. 1 by turning ca-m ring back until latch 37 again locks into notch 38 and thereby forcing chaser carriers 29 onto the high parts of cam rinO 19 so that the chasers are brought together in readiness to work.

TWhat I claim is:

1. In a die head, the combination with a body, of chaser carriers slidably mounted therein, and resilient means for removing said carriers outwardly, a cam ring rotatably mounted on the body and having depressions therein, said carriers having cams thereon adapted to move into the depressions under the influence of the means for moving carriers outwardly, roller bearings between said body and said cam ring, said bearings being so located as to facilitate the movements of the cams from the de.- pressions, and means for locking the cam ring and body together.

2. In a die head, the combination with a body, of chaser carriers slidably mounted therein, a cam ring rotatably mounted on the body and having` high and low portions, said carriers having cams adapted to ride on the` cam surface of said ring, resilient means for moving said carriers outwardly to force the cams into the low portions ot' the cam ring, and roller bearings located at the junction of the low portions and high portions of the cam ring to facilitate the movement of the cams from the former to the latter.

3. In a die head, the combination with a body, of chaser carriers slidably mounted therein, a cam ring rotatably mounted on the body and having' high and low portions, said carriers having cams adapted to ride on the cam surface of said ring, resilient means for moving said carriers outwardly to force the cams intothe low portions of the cam ring, and anti-friction bearings located at the junction of the low portions and high portions of the cam ring to facilitate the movement of the cams from the former to the latter.

4. In a die head, the combination with a body having a slot therein, of chaser carriers mounted in said slot and having cams thereon, said body having channels communicating with the slot, a double bow spring located in said channels and having bearing portions disposed in recesses in the chaser carriers, a face plate closing said channels and having a slot registering with the slot in the body, chasers mounted on the carriers and operable in the slot in the face plate, said chasers closing the recess in the carriers, said body having a reduced portion, a cam ring rotatably mounted on said reduced portion and having an interior face co-operating with cams in the carriers, and anti-friction bearing disposed between body portion and cam ring.

In testimony whereof, Ihave signed my f name to this specification thisllth day of April, 1923.

SERGEI A. SOUNDOUKOFF. 

